Letter-opener.



R. MOCRUM. LETTER OPENER. APPLICATION FILED rBB.1o,191L

1,096,933. Patented May 19, 1914.

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M MM; y f Mft/Mm dmmq R. MOGRUM. LETTER OPENER. APPLIGATION Hmm 11:13.10, 1911.

` Patented May 19, 1914,

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inventor m 1f y@ l @Ziff-MW R. MGCRUM. LETTER OPENER.

APPLICATION ILED TEB10, 1911. 1,096,933. Patented May 19, 1914,

4 SHEETS-'SHEET 4.

y UNITED STATES PATENT OFFICE.

ROBERT MGCRUM, OF LONDON, ENGLAND.

LETTER-OPENER.

Specification of Letters Patent. Application led February 10, 1911. Serial No. 807,754.

Patented May 19, 1914.

To all whom it may concern:

Be it known that I, ROBERT McCnUM, a citizen of the United States of America, residing at 317 High Holborn, in the county of London, England, have invented new and useful Improvements in Letter-Openers, of which the following is a specification.

This invention relates to machines for opening envelops in which the opening is effected by abrading the edge of the envelop or other covering. Hitherto the fine dust produced by these machines has been the source of some trouble and various means have been devised t0 render the dust innocuous. According to the present invention there is combined with the machine a fan or air pump which causes air to pass over the abrading surface while at work and carries the dust with it into a suitable collector.

The` preferred construction of machine as hereinafter described has an abrading roller arranged to' project slightly through an opening in a surface late. Except for the roller this plate is eft absolutely unobstructed so that envelops or packages of any desired size within reason may be opened upon the machine. Preferably an electric motor is provided to operate the machine and this can conveniently be arranged '1n a casing beneath the surface plate together with the abrading roller. In another part of the same casing is a fan for drawing air past the roller and a filter to collect the dust. It is found unnecessary to mechanically clamp the letters when they are to be opened. n the present construction a guide plate is provided against which the letters are held by hand during the operation while an adjacent guard plate prevents any risk of the hands being brought into contact with the abrading roller. These and other novel and important features of the invention are more particularly described in the following specification. y

The accompanying drawings illustrate this preferred construction of machine.

Figure 1 is a cross sectional elevation of the whole machine. Fig. 2 a plan; Fig. 3 a plan with the surface plate removed; Fig. 11 is a detail of the dust collector; Fig. 5 a detail view of the means for adjusting the roller; Figs. 6 and 7 are details of the roller support; Fig. 8 illustrates a feature of the surface and guide plate; Fig. 9 the fixing of one end of the surface plate, the casing inclosing the abrading roller.

and Fig. 10 passes,

Fig. 11 is a further detail of the guide plate and surface plate. Fig. 12 is a partial sectional elevation showin certain modifica tions. Fig. 13 is a detai of the guard plate and surface plate.

As'may be s een from Fig. 1 the whole machlne comprises a base late 1 which may be stamped or cast and is preferably provided with rubber feet 2. Upon this base plate 1s erected a casing 3 preferably also stamped which supports at 1ts top the surface late 4. This has a perfectly smooth and at upper surface with no raised edges or other obstructions whatever. or the sake of lightness it is prefer ably made of aluminium which has the further advantage of not readily corroding. The plate is pivoted by the lugs 5 upon the casing 3. This fixing is seen more clearly in Fig. 9 where a stud 6 is shown passing through the casing 3 and into the lug 5. Approximately in the middle of the plate 4 there is an opening through which protrudes the abradin roller 7. This roller is preferably mounted in ball bearings as shown in Figs. 6 and 7, its spindle having a pulley 8 upon it b which it is driven as hereinafter describe he roller may be made of wood and the abrading surface formed upon it by gluing on particles of flint and French bur. The roller is driven by belt 9 from the electric motor 10, the circuit of which is completed through switch 11 to the plug socket 12. Thus the machine may be operated from an ordinary lamp socket by a suitable connection. The remainder of the casing 3 is occupied by a wooden or other box 13 which contains the fan. This fan which is of the centrifugal type comprises a casing 111 in which rotates a shaft 15; to this are secured curved blades 16 to afford access to the fan; the front wall 17 of its box is made as a sliding lid fitting down over the outlet nozzle 18 of the fan. The opening of this nozzle is obstructed by wires 19 which serve to break up the current of air and lessen the noise. If desired there may in addition be a hood 2O covering the opening. in the casing 13 there is arranged a frame 21 supporting a sheet 22of perforated metal and also a sheet 23 of fine silk gauze. This construction is better seen in Fig. 4:. It will be understood that the metal plate forms a backing for the auze through which the air d but whic obstructs and retains the ust.

It is obviously necessary if full advantage altogether. It is convenient, however, that is to be taken of the fan that ingress of air these sliding parts should be heldin 1n1tial. into the casing 13 should be prevented. exposition at the other end of plate 4 to percept at the place where dust arises; this is mit of adjustment of the guard plate with- 5 on the incoming edge 24 of the slot through out movement of the guide plate. For tlns 70 which the roller 7 rotrudes and of course purpose the frame '28 is provided with on the upper sur ace of Ythe roller also. beveled surfaces 39 (seeFig. 8) which in Accordingly there is arranged around the the end pos1t1on` engage wlth leaf springs roller 7 as seen in Figsfl and 10 a casing 25 40 upon the plate and so frictionally hold 10 upon the upper edges of which are rubber the sliding parts in position. 75 tubes or other packing 26 adapted to t In order to adjust the depthof cut of the against the surface plate 4. If desired the roller 7 the plate 4 is made adjustable m surface plate may be fitted with downwardly height. Since it is pivoted at one end the projecting ianges 50 covered with felt 51 to adjustment is conveniently made by the aid provide this dust-tight joint. A pad 27 of of a central screw `41 (see Figs. 1 to 5) 8o felt in the casing 25 lits close against t-he which is secured in the casing 3 and abuts outgoing surface of the roller 7. This also upon plate 4. This screw has a sultable nut serves to prevent the dust traveling around or milled disk 42 upon it protruding from with the roller and so gives the fan an opthe casing so that it may be easily turned.

portunity of drawing the dust away. The Slotted lugs 43 upon the plate 4 engaging 85 mouth of the casing is also arranged to over screws 44 in the casing 3 inde the plate fit against the edges of an opening 1n the and limit its movement; a o when the box 13, the contacting surfaces being prefscrews 44 are tightened the plate is clamped erably felt covered as indicated at 52 to in its adjusted position, and the selected cut 25 make a good joint. The box 13 can be slid made permanent. 90 out from the casing 3 and t-he surfaces on The driving belt 45 for the fan is preferwhich it moves are covered with felt 53 to ably of round rubber and extends from the lessen the noise and also to minimize any pulley on the shaft of motor 10 to the vibration. Similarly felt stops 54 are propulley 46 on the shaft of the fan. A similar vided against which the casing abuts when pulley 47 is mounted close beside 46 but on 95 in position. the casing 3. When the box 13 is to be For convenience in manipulatin the letwithdrawn the belt 45 is moved from pulley ters there is provided upon the surace plate 46 to pulley 47 so as to leave the fan box a frame 28 having members lying along the free.

sides of the plate and a transverse member In use the surface plate 4l is adjusted so 100 29 across the plate. As may be seen from that the abrading roller 7 projects to the de- Fig. 11 the plate 4 is provided with a sired extent. A number of letters after berecessed run-way upon which the side meming shaken to bring their contents to one bers of frame 28 move, there being preferside .are reversed and placed against the ably ball bearing supports 30 interposed. guide plate 31, the guard plate 32 being suii- 105 The frame 28 carries a vertical guide plate ciently withdrawn to permit letters to be 31 which is set slanting across the surface thrust against surface plate 4. The letters plate 4. Beneath the cross bar 29 of the are then pressed against plate 31, the lingers frame 28 there slides a guard plate 32 which partly resting on plate 32. These two parts also has ball bearings 33 moving upon the are then moved backward and forward once 110 run-way in plate 4 (see Fig. 12). This or twice over the roller which is set-in rotaguard plate 32 is proyided at its end with a tion by the motor 10. The edges of the en- .thumb piece 34 and is` connected to the frame velop 'are thus abraded olf to an extent de- 28 by a spiral spring 35 (see Fig. 2). The pending on the adjustment of the roller and 5o edge of this plate is cut slantwise so as to be the resulting dust is drawn down throu h 115 parallel with the vertical guide plate 31. casing 25 into box 13`underthe action oft e The action of spring 35 is to draw the plates lfan 14, 15, 16. The fan draws the air together so that the opening between them through screen 23 which the dust cannot is diminished. The plate 32 can however, penetrate. The slight inclination of the 1 rbe drawn away and a bunch of let-ters of screen permits the dust to fall readily4 par- 120 desired size inserted between the guide `plate ticularly on .a momentary stoppage of the 31 and the ed e of plate 32. If. desired the motor so that choking is hindered. plateI 32 may e locked in a particular po`si- What I claim is:- tion relative to plate 31 by the aid of screw 1. An envelop opening machine compris- 36 passing through the cross member 29. ing in combination a main framing, any 125 Rubber stops 37 upon the frame 28 serve for abrasive roller revolubly mounted in said the abutment of the supporting members of framing, a casing about said roller, a box plate 32. Stops 38 on the pivoted end of movable in said main framing and adapted the plate 4 (see Fig. 9) serve to prevent the to make joint with the caslng f about the sliding parts 31 and 32 passing olf the plate roller, a dust collector in said box and 13 means in said box for drawing air over the abrasive roller and through the dust collector.

2. In an envelop opening machine the combination of a main framing, a rotatable abrasive roller mounted therein, a surface plate pivoted at one end upon said framing, a screw movable in said framing supporting the other end of said surface late, and guides projecting from the sur ace plate over members attached to the frame to guide the plate and limit its motion.

3. In an envelop opening machine the combination of a slotted surface plate, a rotatable abrading roller protruding there'- through, and a horizontal guard plate'supported a small distance above and parallel to said surface plate and slidable thereon, said guard plate' adapted to support envelops above the abrading roller.

4. In an envelop opening machine the combination of a surface plate, an abrasive roller protruding therethrough, a vertical plate against which envelops may be pressed by the thumbs and fingers, and a broad horizontal plate adjacent thereto, said broad horizontal plate forming a finger rest.

5. In an envelop opening machine the combination of a surface plate an abrasive roller protruding therethrough, a' vertical plate against which envelops may be pressed by the thumbs and fingers, a broad horizontal plate adjacent thereto in position for the fingers to rest upon, means normally drawing said horizontal plate toward the vertical plate, and means for securing the plates in definite relative position.

(S. In an envelop opening machine the combination of the main framing, an abrasive roller rotatably mounted therein, a surface plate slotted to permit rotrusion of the roller pivoted at one end o the framing, a guide plate sliding on `said surface plate, and means at the end of said surface plate operating lautomatically vto irictionally engage the said guide plate and retain it when the surface plate is raised.

7. In an envelop openin combination with a main ramin of an abrasive 'roller rotatably mounted t erein, a surface plate slotted toI permit protrusion face plate said roller,

machine the of said roller, a pad making close joint with said roller on one side thereof, a casing surrounding said roller, means for making joint between said roller and the surface plate, and a dust collector abutting upon the casing surrounding the roller.

8. In an envelop opening machine the combination with `an abrasive roller, of a casing about said roller, a box making joint with said casing, a fan in said box, a gauze screen interposed between said fan and said roller, and means for dispersing the air expelled by said fan so as to lessen the noise produced thereby. j

9. In an envelop opening machine the combination with a mam framing, an abra' sive roller rotatably mounted therein, a sur.- slotted to permit protrusion of a fan removable from said casing, a ulley upon said fan, an electric motor, be ts joining said motor to the roller and to the pulley on the fan and a second pulley similar to and adjacent to that upon the fan secured to the framing.

10. In an envelopv opening machine the combination of a main casing, a slotted surface plate thereon, an abrasive roller revolubly mounted in said casing and protruding through said slotted surface plate, felt stops and surfaces in said main casing, a box sliding on said surfaces and abutting on said stops, and a fan and dust collector in said box.

11. In an envelop opening machine the combination of a main casing, a slotted surface plate pivoted roller revolubly mountedl in said casing and protruding through said surface plate, a casing about said roller, means making close joint between said casing and the surface plate, a fan within the main casing, adapted to draw air over the roller, and a dust collector interposed between said fan and the roller casing.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ROBERT MCCRU'M.

Witnesses:

M. A; YOUNG LEON ARD E. Armas.

thereon, an abrasive` 

